Description
The ACT Mod-Twin 225 Heavy Duty Sprung Race Clutch Kit is engineered for high-powered BMW B58 and Toyota GR Supra applications where maximum torque capacity, aggressive launches, rapid shifting, and dependable race-level durability are required. With a substantial 1,060 ft/lbs of torque capacity, this ACT twin-disc clutch provides 122% more torque capacity than the OE clutch, making it an ideal choice for demanding drag, road, and rally racing applications.
The T1RS-B02 Mod-Twin 225 HD Sprung Race Kit combines two ceramic friction surfaces with an ultra-durable sprung Mono-Drive hub assembly in a fully modular design. The sprung hub helps absorb torsional vibration, reduce driveline shock, and extend transmission input shaft life while maintaining the aggressive engagement characteristics required for competition use.
Puck-style friction plates with high-quality ceramic friction material provide a high coefficient of friction, exceptional heat capacity, and long service life under severe operating conditions. Each diaphragm spring undergoes ACT's exclusive four-stage heat-treating process to provide consistent clamping performance and light pedal effort.
The ACT Mod-Twin 225 HD Sprung Race clutch uses a CNC-machined and dynamically balanced flywheel, pressure plate cover, diaphragm spring, ceramic friction plates, sprung Mono-Drive hub assembly, floater, patented Monoloc Collar, release bearing, alignment tool, and pilot bearing when required. The Mod-Twin platform is fully rebuildable, with most components available separately for long-term serviceability.
Fitment
BMW 3.0L Turbo B58 Applications
- 2016–2018 BMW 340i
- 2016–2018 BMW 340i xDrive
- 2017–2018 BMW 440i
- 2017–2018 BMW 440i xDrive
- 2017–2021 BMW M240i
- 2019 BMW 440i
- 2019 BMW 440i xDrive
- 2019 BMW M240i
Toyota GR Supra 3.0L Applications
- 2023 Toyota GR Supra A91-MT Edition
- 2023–2026 Toyota GR Supra Base
- 2023–2026 Toyota GR Supra Premium
- 2023 Toyota GR Supra Special Edition
- 2024 Toyota GR Supra 45th Anniversary Edition
- 2024 Toyota GR Supra Premium 45th Anniversary Edition
- 2024 Toyota GR Supra Special Edition
- 2026 Toyota GR Supra A90 Final Edition
- 2026 Toyota GR Supra MkV Final Edition
Engine: 3.0L L6 gasoline, 2998cc, DOHC
Key Features
- ACT Mod-Twin 225 Heavy Duty Sprung Race Clutch Kit
- Part Number: T1RS-B02
- 1,060 ft/lbs torque capacity
- 122% greater torque capacity than OE
- Twin ceramic friction surfaces
- 225 mm / 8.8-inch clutch disc diameter
- Sprung Mono-Drive hub assembly
- Heavy Duty pressure plate
- High-friction ceramic puck-style friction plates
- High heat capacity
- Predictable aggressive engagement
- Light pedal effort
- Quick shifting performance
- Potential start-off judder
- OE to mild-to-moderate transmission gear noise
- CNC-machined and dynamically balanced flywheel
- Forged aluminum cover
- Patented Monoloc Collar
- Fully rebuildable modular design
- Designed for Drag, Road, and Rally Racing
- Clamp-load tested, balanced, and SFI certified
Specifications
| Specification | Details |
|---|---|
| Brand | ACT |
| Part Number | T1RS-B02 |
| Item Description | ACT Mod-Twin 225 Heavy Duty Sprung Race Clutch Kit |
| Product Weight | 33.1 lbs |
| Torque Capacity | 1,060 ft/lbs |
| Torque Capacity Over OE | 122% |
| Disc Material | Ceramic |
| Clutch Disc Diameter | 8.8 inches / 225 mm |
| Input Shaft Diameter | 1.375 inches |
| Pressure Plate Type | Heavy Duty |
| Recommended Use | Drag / Road / Rally Racing |
Performance and Durability
Feel: The ACT Mod-Twin 225 HD Sprung Race clutch provides predictable, aggressive engagement, light pedal effort, and quick shifting. Depending on the vehicle and drivetrain configuration, some start-off judder and OE to mild-to-moderate transmission gear noise may occur.
Life: The forged aluminum cover, sprung Mono-Drive hub, specially treated diaphragm spring, premium ceramic friction materials, and hardened wear points are designed to withstand severe racing conditions while providing long service life.
Quality: ACT combines robust construction, carefully selected materials, close manufacturing tolerances, and high heat tolerance to deliver maximum performance under demanding race conditions.
ACT Difference: ACT applies tactical engineering to the Mod-Twin platform to address common compromises found in twin-disc clutch systems. The result is a high-capacity, durable, serviceable clutch designed for extreme performance applications. ACT clutch assemblies are clamp-load tested, dynamically balanced, and SFI certified.
Break-In Recommendations
For ACT race discs, only a short break-in process is generally required. ACT recommends a few controlled hard slips to properly lap the friction surfaces before normal driving or racing. Avoid excessive overheating during break-in, as this can cause friction surfaces to fuse together, create hot spots, or glaze the friction material.
Frequently Asked Questions
Are ACT clutches balanced?
Yes. ACT clutch assemblies are computer spin-balanced to within 0.25 oz-in to help ensure smooth operation throughout the RPM range. Stock production clutches are typically balanced to within approximately 0.50 oz-in.
Will an ACT clutch increase pedal effort?
ACT pressure plates are designed for high-torque applications. Depending on the application, Heavy Duty pressure plates can increase pedal effort by approximately 15–40%, while Xtreme pressure plates can increase pedal effort by approximately 50–80%. The increased clamping force helps provide the torque capacity, durability, and engagement characteristics required for performance applications.
Do ACT race clutches require a break-in period?
ACT race discs generally require only a few controlled hard slips to properly lap the friction surfaces before normal driving or racing. Avoid overheating the clutch during this process.
Are ACT clutches repairable or rebuildable?
The ACT Mod-Twin is designed as a modular and rebuildable clutch system. In some cases, repairs or rebuilding may be possible following inspection of the clutch assembly. Due to the specialized construction and modifications involved, ACT recommends having the clutch serviced by qualified technicians familiar with Mod-Twin systems.
How much does the ACT clutch weigh?
The ACT Mod-Twin 225 HD Sprung Race clutch assembly weighs approximately 33.1 lbs and is generally comparable to the weight of a stock OEM clutch assembly.
